1. Field of the Invention
This invention relates to a foldable machine intended to be used for various tasks such as the handling, lifting and placing of loads, particularly at the construction sites of small buildings such as small apartment houses and small office buildings.
2. The Prior Art
It was known to assure the handling, lifting and placing of loads at construction sites by using a mobile crane equipped with a retractable telescopic jib. However, a number of drawbacks attend the use of the mobile crane because of its configuration. The ground space required is considerable, which calls for a sufficiently extended clearance area. This space can be hard to find in some cases. Additionally, the height under the hook necessary to reach the farthest points of the building under construction is clearly greater than the useful height for the construction site.
It is also known to use a standard tower crane with an automated assembly, which is equipped with a flexible or telescopic mast and a placing or derricking jib at the top of the mast. The jib is either telescopic or constructed of two or more elements joined to one another. The presently used embodiments of this type exhibit the following drawbacks. The clearance area necessary for unfolding the crane, particularly its jib, is considerable. Additionally, the unfolding devices generally comprise metal cables which follow more or less complicated paths and require considerable assembly preparation time and manual intervention. Further, automation of the work of the crane is difficult to achieve.
The invention aims at reducing the drawbacks presented by the two preceding solutions. In particular, the invention is designed to reduce the clearance area necessary for putting the machine into operation, to match the height under the hook with the needs of the site, to allow rapid placement without manual intervention and thus to improve the safety and profitability, and finally to permit automation of the work of the machine.